This photograph depicts two adolescent or pre-teen boys with a Jeffery Manufacturing model 28A mining machine, ca. 1890-1910. The mining machine was used to undercut seams of coal, to allow for expansion after the coal seam was broken apart with explosives; at the time of its invention, this was the most time-intensive part of mining coal. Jeffery Manufacturing was located in downtown Columbus, near the intersection of Fourth St. and First Ave. Today, that site is occupied by the Ohioana Library and the State Library of Ohio, as well as a luxury housing space known as "the Jeffrey."